1. Field of the Invention
The present invention relates to an acoustic signal transmitting system capable of discriminating a large number of mutually independent acoustic signals fed from a large number of acoustic input means such as microphones into an acoustic processing means such as a recording apparatus.
2. Prior Art
In general, when mutually independent acoustic signals are input into an acoustic signal processing means such as a recording apparatus through a plurality of acoustic input means such as microphones, it is possible to mix the outputs from the microphones by means of a mixing apparatus and to input the mixed output into an acoustic signal processing means by an input apparatus for a single channel.
However, in the case where it is intended to discriminate the output signals from individual microphones or the like at the side of an acoustic processing means (a utilizing means), it is necessary to provide an input apparatus for a single channel to each of microphones or the like.
In this regard, there are also available processes by which it is made possible to discriminate the independent acoustic signals at the side of an acoustic processing means in such a manner that a plurality of mutually independent acoustic signals are transmitted through a single transmission channel by multiplexing a plurality of input acoustic signals by a frequency multiplex system, which operates with carrier frequencies differentiated for the individual signals in a plurality of acoustic signals, or by a time division multiplex system through digitalization of such signals.
Also, the voice input apparatus disclosed in Japanese Patent Unexamined Publication No. Sho 63-116199 is constructed in such a manner that it is capable of registering the voice patterns of a plurality of specific speakers in advance and discriminating the individual speakers who have pronounced vocal sounds fed into the apparatus. This apparatus receives a specific vocal command from an operator to load the vocal dictionary associated with the operator using voice recognition techniques.
In addition, Japanese Patent Unexamined Publication No. Sho 63-3589 discloses a television conference system, as related technology, which is constructed in such a manner that the system discriminates the speakers on the basis of the output from microphones and automatically directs a television camera towards the particular speaker who has pronounced the vocal sounds. The Television Conference System determines which of a plurality of microphones is generating the highest level of output. This microphone is identified and a look-up table is used to determine which corresponding camera should be activated.
However, the prior art technology described above requires that an acoustic transmitting apparatus should be provided with a mixing apparatus or provided with a multiplex apparatus, so that such an acoustic transmitting apparatus accompanies the problems that the acoustic transmitting apparatus as a whole is necessarily large in its construction and that it is difficult for such an apparatus to be formed in a simple construction and yet to discriminate the individual items of acoustic input means, such as microphones.
Moreover, an acoustic transmitting apparatus which employs a multiplexing system is limited in respect of the number of signals which can be fed into the system, in consequence of the frequency band width and frequency characteristics of the transmitted signals, and such an acoustic transmitting apparatus therefore accompanies the problem that it is difficult for such an acoustic transmitting apparatus to deal properly with signal transmission required in the case where the number of input signals is extremely large.
Further, technology such as that disclosed in Japanese Patent Unexamined Publication No. Sho 63-116199 accompanies the problem that the construction of an apparatus embodying the technology will necessarily be large in its construction because an acoustic processing means having a complicated construction such as a voice recognizing apparatus and so on is indispensable to such an apparatus for discriminating the individual speakers, namely, the input signals fed from the individual microphones.